Debris from the Airbus is landed at Recife port, Brazil, before being taken to Paris to be examined by crash investigators. Photograph: Reuters

The first body to be recovered from the sunken wreckage of Air France Airbus that crashed in June 2009 en route from Rio to Paris has been retrieved from the bottom of the Atlantic, still strapped to a seat.

French gendarmes said the partially decomposed remains had lain at a depth of almost 2.5 miles since flight 447 went down on 1 June, 2009. The body, brought to the surface by mini-submarines, will now be DNA tested before being taken to France.

Rescuers said the search, using sea robots to recover bodies from the ocean off Brazil, is complex and "unprecedented". Experts said that the cold and lack of oxygen at that depth could mean bodies were comparatively well preserved. But they could rapidly decompose on being moved through warmer surface waters and into the air.

In the days after the crash about 50 bodies and parts of the plane were pulled from the sea by the Brazilian navy, but after that nothing was found for almost two years.

Earlier this week the black boxes and cockpit voice recorder were recovered, which could help explain the crash in which all 228 people on the Airbus A330 died.

The quest to recover bodies from the ocean is controversial among victims' families. Some fear it will further traumatise relatives, others are concerned about the state of the remains two years after the crash.

One relative, Corinne, whose daughter, Caroline, and her husband died in the crash, told French TV she was against the mission. "I wanted Caroline to rest in peace at the bottom of the ocean, because for me that was her final resting place and tomb. To think she could be hauled up to the surface hugely perturbs me because they are going to disturb that rest which began two years ago for her."

Other families were keen for remains to be recovered in order for closure. The brother of one victim said: "I want to be able to start the grieving process. It's very sad to have my brother at the bottom of the ocean. I want him to be brought up to the surface so we can bury him and have a place to go to remember him."